The proposed program of research is intended to help clarify the structure and construction of consistency in social behavior. The key issues here concern the nature of the consistencies, over time and across contexts, that characterize social behavior and the construction (social perception) of consistency in personality. Theoretically, the work is guided by a synthesis of cognitive social learning theory and a prototype approach to the categorization of social behavior and situations. Methodologically, the program utilizes a series of larger scale observational field studies to test hypotheses about the nature and construction of consistency and utility of alternative ways of conceptualizing and categorizing the data. In the initial phases, two dimensions of social behavior, conscientiousness and friendliness, will be extensively assessed over time and across contexts in samples of college students living in a small residential campus. The focus will be on the temporal stability and cross-situational consistency of the students' behavior catergorized in various theory-guided ways, and on the links between these behaviors and indices of perceived consistency and prototypicality. Throughout, we will employ a broad range of measures, from the molecular to the more molar. A number of potentially relevant moderator variables (e.g., perceived cross-situational variability, self-monitoring, self-schemata) will also be included. Other dimensions of social behavior will also be explored with the same general method in selected samples of children.